The following problems below may be exhibited by liquid crystal display devices (liquid crystal displays) using TFTs (thin film transistors) with excellent OFF characteristics, such as TFTs having oxide semiconductors, in a drive device. Such TFTs have favorable OFF characteristics and low leakage current when OFF. Thus, charge may remain in the pixels even after the power is turned OFF, which may result in a long period of DC potential (direct current potential) being applied to the liquid crystal. In other words, if charge remains between pixel electrodes when the power is OFF, the charge will be held for a long period of time, which could result in screen burn-in, liquid crystal degradation, or the like.
Patent Document 1 discloses a technique for obviating the continuous application of voltage on liquid crystal when the power of the liquid crystal display is OFF. In the liquid crystal display described in Patent Document 1, before the power is stopped, a fixed potential is written to the capacitive elements of all of the pixels, and an initialization image is displayed with almost zero difference in potential between the electrodes of the capacitive elements. After the difference in potential between the electrodes of the capacitive elements is approximately zero, the power supply is stopped. In other words, an OFF sequence is performed when turning OFF the power whereby a fixed potential is written such that liquid crystal application voltage becomes 0V, and, after this fixed potential is written, the power is turned OFF.